Microelectromechanical devices, such as switches or relays, may be used as alternatives for conventional electromechanical devices. Advantages to microelectromechanical devices built using conventional semiconductor processes are programmability and reduced size, enabling smaller form factors and a corresponding reduction in power consumption, response time, and cost.
One application that uses conventional microelectromechanical switches and relays is telecom switching gear. In these applications, a microelectromechanical switch or relay may be engaged in one position for a time ranging from weeks to years. It is known that metals under external forces, as found in, for example, components of a microelectromechanical switch and relay, show a permanent deformation when the external force is removed. This phenomenon is known as mechanical creep. If the deformation caused by mechanical creep is great enough, such as found from extended closures of a microelectromechanical switch or relay, the microelectromechanical switch or relay can be rendered unusable over time.
It is not uncommon to find reliability requirements in the telecom industry that demand a lifetime of usage of a device to be 15-20 years. Given this requirement of the telecom industry and mechanical creep inherent in metal microelectromechanical switches and relays, conventional microelectromechanical devices may not meet the need of the telecom industry.
Accordingly, what is needed in the art is microelectromechanical switch or relay that will meet a long term reliability requirement such as found in the telecom industry.